In:
FEBS Letters, Wiley, Vol. 379, No. 3 ( 1996-02-05), p. 231-235
Abstract:
The binding of Fe(III) to F 1 ATPase purified from beef heart mitochondria has been characterized by chemical analyses and EPR spectroscopy. F 1 ATPase binds 2 of Fe(III)/mol of protein selectively in the presence of saturating concentrations of ATP. In the absence of nucleotides or in the presence of either saturating ADP or limiting ATP concentrations, the enzyme binds 1 equivalent of Fe(III). F 1 ATPase pretreated with 5′‐ p ‐fluorosulfonylbenzoyladenosine, that selectively modifies the noncatalytic sites, binds only 1 mol of Fe(III)/mol of protein in the presence of either saturating ATP or ADP. Fe(III)‐loaded F 1 ATPase containing either 1 or 2 equivalents of Fe(III) show identical EPR signals at g = 4.3. The signals are not perturbed by the binding of nucleotides to the enzyme while they are altered by phosphate addition. These results indicate that F 1 ATPase contains two distinct Fe(III)‐binding sites, which differ from nucleotide‐binding sites, and that one of these sites is opened up for Fe(III) uptake by conformational changes induced by binding of ATP to the loose non‐catalytic site.
Type of Medium:
Online Resource
ISSN:
0014-5793
,
1873-3468
DOI:
10.1016/0014-5793(95)01517-5
Language:
English
Publisher:
Wiley
Publication Date:
1996
detail.hit.zdb_id:
1460391-3
SSG:
12